Restructure project layout to flatten directory structure

Move all projects from Source/ to repository root for simpler navigation.
- Remove External/ dependency DLLs (will use NuGet packages)
- Remove Installer/ NSIS script
- Replace PartCollection/PlateCollection with ObservableList
- Add packages.config for NuGet dependencies

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

OpenNest.Core/CNC/RapidMove.cs

@@ -0,0 +1,42 @@
+
+namespace OpenNest.CNC
+{
+    public class RapidMove : Motion
+    {
+        public RapidMove()
+        {
+            Feedrate = CNC.Feedrate.UseMax;
+        }
+
+        public RapidMove(Vector endPoint)
+        {
+            EndPoint = endPoint;
+        }
+
+        public RapidMove(double x, double y)
+        {
+            EndPoint = new Vector(x, y);
+        }
+
+        public override CodeType Type
+        {
+            get { return CodeType.RapidMove; }
+        }
+
+        public override ICode Clone()
+        {
+            return new RapidMove(EndPoint);
+        }
+
+        public override string ToString()
+        {
+            return ToString(DefaultDecimalPlaces);
+        }
+
+        public override string ToString(int decimalPlaces)
+        {
+            var dp = "N" + decimalPlaces;
+            return string.Format("G00 X{0} Y{1}", EndPoint.X.ToString(dp), EndPoint.Y.ToString(dp));
+        }
+    }
+}